Drain Current Characteristics of Enhancement Mode GaN HEMTs

A drain current model of AlN/GaN based MIS-HEMTs and ridge (GIT) HEMTs has been developed for source-field-plate structures. Characteristic differences in these two structures are theoretically and experimentally analyzed with measurements of fabricated devices. For ridge HEMTs, hole injection current and leakage current of gate interface are focused on, whereas the MIS-HEMTs use a MOSFET gate modeling approach. Because the simulation results show good agreements with the measurements, one model can be applied to both MIS and ridge HEMTs to design power supply circuits.